PROLOGUE: I AM A MYSTERIAN

Our brain is a small lump of organic molecules. It contains some hundred billion neurons, each more complex than a galaxy. They are connected in over a million billion ways. By what incredible hocus-­pocus does this tangle of twisted filaments become aware of itself as a living thing, capable of love and hate, of writing novels and symphonies, feeling pleasure and pain, with a will free to do good and evil? Let me spread my cards on the table. I belong to a small group of thinkers called the “mysterians.” It includes , Colin McGinn, , also , Roger Penrose, and a few others. We share a conviction that no or scien- tist living today has the foggiest notion of how con- sciousness, and its inseparable companion free will, emerge, as they surely do, from a material brain. It is impossible to imagine being aware we exist without having some free will, if only the ability to blink or to decide what to think about next. It is equally impos- sible to imagine having free will without being at least partly conscious. In dreams one is dimly conscious but usually with- out free will. Vivid out-­of-­body dreams are excep- PROLOGUE tions. Many decades ago, when I was for a short time taking tranquilizers, I was fully aware in out-­of-­body dreams that I was dreaming, but could make genuine decisions. In one dream, when I was in a strange house, I wondered if I could produce a loud noise. I picked up a heavy object and flung it against a mir- ror. The glass shattered with a crash that woke me. In another OOB dream I lifted a burning cigar from an ashtray and held it to my nose to see if I could smell it. I could. We mysterians are persuaded that no computer of the sort we know how to build—­that is, one made with wires and switches—­will ever cross a threshold to become aware of what it is doing. No chess pro- gram, however advanced, will know it is playing chess any more than a washing machine knows it is wash- ing clothes. Today’s most powerful computers dif- fer from an abacus only in their power to obey more complicated algorithms, to twiddle ones and zeroes at incredible speeds. A few mysterians believe that science, some glorious day, will discover the secret of . Penrose, for example, thinks the mystery may yield to a deeper understanding of quantum mechanics. I belong to a more radical wing. We believe it is the height of hubris to suppose that evolution has stopped improv- ing brains. Although our DNA is almost identical to a chimpanzee’s, there is no way to teach calculus to a chimp, or even make it understand the square root of 2. Surely there are truths as far beyond our grasp as our grasp is beyond that of a cow. Why is our universe mathematically structured? Why does it, as Stephen Hawking recently put it,

xxvi I AM A MYSTERIAN bother to exist? Why is there something rather than nothing? There may be advanced life-­forms in Andromeda who know the answers. I sure don’t. And neither do you. Martin Gardner, August 2007 Excerpted from “Do Loops Explain Consciousness? Review of I Am a Strange Loop,” Notices of the AMS 54, no. 7 (August 2007). Published by the American Mathematical Society.

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UNDILUTED HOCUS-­POCUS